Statistical relations between the luminosity L of gamma-ray burster (GRBs) and several of
their other observable properties have been discovered. Four of these properties are considered
here: the spectral lag; a measure ...

A strong correlation between the gamma-ray burster peak energy and the peak luminosity
of the associated supernova was discovered by Li for four GRBs. Despite the fact that the
formal significance level of the correlation ...

The dependence of [Fe/H] on galactocentric distance, distance from the galactic mid-plane
and age is studied. Both ordinary least-squares and non-parametric regression in the form of a
‘generalized additive model’ are ...

We present homogeneous and standardized UBV(RI)C JHK photometry for over 100 M stars
selected from an earlier paper on the basis of apparent photometric constancy. L photometry
has been obtained for stars brighter than ...

HE 0230−4323 is a hot sdB star in a binary system. An earlier work demonstrated that the
light curve of the system shows a strong (∼4 per cent) reflection effect and also appears to
exhibit photometric variations of the ...

Possible deviations from linearity of the Large Magellanic Cloud Cepheid period–luminosity
(PL) and period–luminosity–colour (PLC) relations are investigated. Two data sets are studied,
respectively from the Optical ...

The paper is based on the notion that the Nyquist frequency νN is a symmetry point of the
periodogram of a time series: the power spectrum at frequencies above νN is a mirror image
of that below νN. Koen showed that the ...

‘Quasi-periodic’ or ‘solar-like’ oscillations can be described by three parameters – a characteristic
frequency, a coherence time (or ‘quality factor’) and the variance of the random
driving process. This paper is concerned ...